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12-06-2013, 06:18 AM   #1
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DA21 sharpness at infinity

I'm looking for some input on how my DA21 is rendering at infinity. I'm new to DSLR's, purchasing both a K5 and a DA21 only this past September, so I don't have much of a baseline for comparison. Up till now, I've shot only "pseudo macros" and street scenes, and have been very pleased with the sharpness of the images. Recently, though, I've taken some shots near infinity and have found them not to hold up to any sort of crop.

Not discounting operator error (a real possibility) I was wondering if some of you might give me an opinion on the sharpness of this image, bearing in mind that it was handheld:

[IMG][/IMG]

What I'm curious about is whether falls within your definition of acceptable sharpness, or whether I need to pursue either better calibration with my camera, or consider sending the lens in for repair.

Here's another shot--this time taken with a tripod and with the 2-second shutter delay:[IMG][/IMG]

Thanks for taking time to help out--any thoughts on a future course of action greatly appreciated!

12-06-2013, 06:41 AM - 1 Like   #2
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I am not sure what exactly you are doing, but here is some general info about sharpness:

a) The DA21mm isn't the sharpest lens in the world. On the other hand, macro lenses are often spectacularly sharp. This means maybe you are used to sharper lenses, but that doesn't mean the DA21mm is bad. I have the DFA 100mm macro and it beats pretty much all my lenses in terms of sharpness and amount of detail rendered. But on the other hand, it doesn't have as much character as some other lenses. Sharpness is not everything
b) To get optimal sharpness you have to use a sturdy tripod and 2 sec timer, low ISO (so the photo isn't fuzzy) and an aperture value that gives you the DoF you need.
c) Environmental effects can make things look unsharp. Atmosphere might not be clean, there might be a breeze moving the leaves and grass, wind shaking the tripod, etc.
d) Post processing is important. If you look at the top notch "pro" photos, they all sharpen their photos a lot in post. Some just shoot raw and use the Sharpness slider, others use plugins and addons, some even use complicated techniques. If you shoot raw, you need to sharpen it up correctly. Be careful with noise reduction, as some NR can cause details to vanish, which makes the photo look soft like a painting.
e) AF or MF? The problem is that many modern lenses do not have a correctly labelled infinity. Some lenses allow focus past infinity, others have no labels at all, and some have a label, but its wrong. This makes MF difficult and confusing. AF might not be very useful when it comes to near infinity subjects, because you often want to zone focus rather than just dial to infinity. You can try using Live view contrast-detect AF btw. For better focus, you can either get the lens and camera calibrated (together) or learn how to focus to get what you want.
Reason why so many lenses have a poor focusing ring these days is that they have a short focus throw for faster AF, and they have space for "error" (so they go past infinity. This allows lower QC standards and allows the lens to be used in many different temperatures, since materials expand). For the average user, this is not a problem. If you seek perfection, it might be an obstacle.

Beyond that, I don't think your examples are unsharp or bad. But there is a learning curve with wide angle lenses and processing them correctly. Also, the DA 12-24mm is probably sharper than the DA 21mm. I think the DA 21mm was mostly meant for street photography and group photos, and the DA 14mm and DA 15mm were meant for landscapes, but I don't actually have experience with them DA 21mm, so I can't give you more specific tips. Ive seen some great landscape photos posted to this forum taken with the DA 21mm. Feel free to check the sample photo gallery.

Last edited by Na Horuk; 12-06-2013 at 06:56 AM.
12-06-2013, 07:16 AM   #3
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The DA 21 has a flaw sometimes - it loses infinity focus and needs to be repaired/adjusted so it can reach infinity. It's not a common problem, but it has happened to my DA 21 so I looked into it.

100% crop the day I bought my DA 21 - using autofocus:



100% crop a few months after - using manual focus and this was the best it could do:



I was able to repair my infinity focus, but in the process I broke the autofocus of my lens. So I would advise - send the lens in for adjustment, don't do it yourself. Looking at your first picture, while I can make out the individual brick details in the building, I see that going further past (for example, the tower on top) is blurry. If there is nothing you can do to get distant objects sharp using manual focus, then your lens is suffering what mine did.
12-06-2013, 08:04 AM   #4
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Na Horuk-- Thank you very much for your reply: I picked a couple of "un-sharpened" photos so everyone could see what was coming out of my camera. I will definitely start exploring the most efficient method for focussing, although since I'm an eyeglass wearer (pretty severe myopia) so right off the bat I'm at a disadvantage whatever method I choose.

Jin-- Thanks for your input: those pictures of yours really have me wondering if I might have the same problem. I'll start to get a bit more organized in terms of really evaluating the problem, and will definitely take your advice about not making it a DYI project! One of the things that was a bit confusing to me was that my assumption that DOF at f8 would be deep enough that I wouldn't have many focussing issues at that distance--at the very least your example shows that to be false.

At any rate, I'm finding the Limited primes as addictive as everyone says--hopefully I can get this one to behave soon.

12-06-2013, 08:14 AM   #5
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I purchased my DA21 used and found it was wayyyy too soft at 3.2. I sent it in to C.R.I.S. For repair and alignment. $123 later and it's like a new lens.
12-06-2013, 08:23 AM   #6
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Let me put it this way - the DA 21, while often maligned as soft at F3.2, is one of the sharpest lenses I know once you stop down past F4. At F5.6 and F8, it was resolving so well that I was surprised by it. And I have a Sigma 50 F1.4 and a Tamron 70-200, and those are no slouches. I'm not saying the DA 21 was sharper than those two (hard to compare anyways), but on my k-x it was amazingly sharp.

Which makes it all the more depressing to make that I broke the autofocus on it. So if you test your lens and cannot seem to get sharp images at infinity, definitely have it sent in.
12-06-2013, 08:26 AM   #7
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Driline-- Thanks! I remember your thread where you were hashing out the AF issues as well...one of the things I was trying to figure out was whether this was a run-of-the-mill back/front-focus issue or something more substantial. Glad to hear that yours is working fine, though--I'm finding I really love the lens, especially as a walk-around outfit.
12-06-2013, 08:40 AM   #8
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Jin-- I was surprised from the beginning about the DA21's sharpness as well--this is a crop of one of the first photos I made with it. That's why I was a bit taken aback by the "infinity" issues I seem to be having.




12-06-2013, 09:00 AM   #9
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I'm amazed at all the bashing this lens gets and then I look at the pictures it produces and wonder why?


12-06-2013, 12:38 PM   #10
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QuoteOriginally posted by CreationBear Quote
I will definitely start exploring the most efficient method for focussing,
Live view.
12-06-2013, 12:40 PM   #11
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I still haven't gotten to use my 21 as much as I would have liked, but so far I can say it's plenty sharp wide open close up. I was pleasantly surprised. Where mine seems weaker is edge sharpness at infinity, even at f/8. Not really bad, but I had expected somewhat better. The center looks good, though.

Happy with all-in-all, just had its real strengths in other areas than I expected
12-06-2013, 01:22 PM   #12
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My marketplace DA21 just arrived, and it too is happier with close shots. I'll dial in some AF adjustment and see how it likes it
12-06-2013, 01:53 PM   #13
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Thanks for taking time to reply, everyone.

Jim-- I'd really be appreciative if you'd post your AF calibration results...I'm assuming from your comments that your version is also soft at infinity?
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